用过SQL Server视图设计或Access查询设计的都见过这样的控件，控件外形象一个窗体，有边框、标题栏、图标、关闭按钮，可拖动、改变大小-View the design used by SQL Server or Access query design have all seen this kind of control, outside the image of a form control, have borders, title bar icon, the Close button